Golf club head

ABSTRACT

The present invention resides in a golf club head having a high COR that is durable and has desirable acoustic qualities. The club head includes a body portion, a striking face and a crown forming a hollow cavity of at least 150 cc in volume. The body portion defines a front opening and an upper opening, and it includes a sole and a side section that extends rearward of the front opening. The striking plate is secured to the body portion, enclosing the front opening. While partially assembled, final weighting and/or other attachment of other members to the inner surface of the club head can be preformed, as desired. The crown is secured to the body portion, enclosing the upper opening. A surface veil may also be provided about a junction of the crown and body. The crown has a maximum thickness no greater than about 2 mm. The density of the crown is less than the density of the body portion. At least one of the striking plate and the crown is attached to the second portion by adhesive bonding, and the golf club head has a maximum coefficient of restitution of at least 0.80.

CROSS REFERENCE TO RELATED APPLICATION

This application is a continuation-in-part of application Ser. No.10/316,453, filed Dec. 11, 2002, now U.S. Pat. No. ______, which isherein incorporated by reference for all purposes.

BACKGROUND OF THE INVENTION

The invention relates generally to a wood-type golf club head and, moreparticularly, to a golf club head having a lightweight crown.

A wood-type golf club head includes a load-bearing outer shell with anintegral or attached strike plate. Today's club head is typically formedof metal material and has a hollow cavity. The metal body may compriseseveral portions welded together or may include a cast body with aseparate sole plate or strike plate that is welded in the appropriatelocation.

Most club heads today are made of a strong, yet lightweight metalmaterial such as, for example, a titanium, steel or aluminum alloy.There have also been heads formed of carbon fiber composite material.The use of these materials is advantageous for the larger club heads nowsought by golfers, i.e., at least 300 cc and up to about 500 cc involume. The larger sized, yet conventionally weighted, club heads striveto provide larger “sweet spots” on the striking face and club moments ofinertia that, for some golfers, make it easier to get a golf ball up inthe air and with greater accuracy.

Various attempts have been made to attain an improvedcoefficient-of-restitution (“COR”) for golf club heads, with muchattention paid to the design of face plates having variable thickness.However, the durability of very thin portions of the face platecontinues to be a problem. Such face plate designs are limited by thehigh impact loads to which these club heads are subject, in particularat the junctions of the face plate with the crown and sole of the clubhead.

Titanium alloys are particularly favored in club head designs for theircombination of strength and light weight. However, the material can bequite costly. Steel alloys are more economical; however, since thedensity of steel alloys is greater than for titanium alloys, steel clubheads are limited in size in order to remain within conventional headweights while maintaining durability.

Composite club heads, such as a carbon fiber reinforced epoxy or carbonfiber reinforced polymer, for example, are an alternative to metal clubheads. A notable advantage is the relatively light weight compared tostainless steel alloys. However, these club heads have suffered fromdurability and performance qualities associated with compositematerials. These include higher labor costs in manufacture, undesirableacoustic properties of the composite material, shearing and separationof the layers of composite plies used to form the striking surface ofthe club head and relatively low COR for composite faces.

The areas of the club head that are subject to the greatest wear, theface and sole, have been reinforced in some instances by providing ametal plate in one or both regions. Integrated face and hoselconstructions have also been done. However, durability at the junctionsof the composite and metal materials continues to be a problem. Further,when the majority of the body of the club head is of composite material,there may still remain the problem of adequately fixing one or moreweighting elements within the head body. The mere increase in volume ofthe club head may not provide the proper location of the center ofgravity of the club head for greater forgiveness in off-center hits.

With regard to hybrid metal-composite club heads, U.S. Pat. Nos.5,328,176, 5,410,798, and 5,624,331 to Kun-Nan Lo disclosecomposite-metal golf club heads having a metal casing with an innermember or core of composite material. The inner member reinforces thethin walls of the metal casing in U.S. Pat. Nos. 5,410,798 and5,624,331. The crown comprises one or two carbon fiber compositeportions. The single composite crown portion of U.S. Pat. No. 5,410,798is attached to the upper ends of the composite member during the heatingportion of the manufacturing process. The double composite crownportions of U.S. Pat. No. 5,624,331 are separated by a reinforcingcentral rib of the metal casing. U.S. Pat. No. 5,328,176 discloses ametal reinforcing plate that is fixed to the front face and wraps aroundthe composite head from front to back.

Published U.S. Patent Application No. 2002/0049310 to Cheng et al.discloses a metal golf club head having a carbon-fiber cover thatincorporates the entirety of the upper wall and a majority of the sidewalls at the toe, rear and heel ends of the head body. The position ofthe center of gravity of the head is accomplished by the size andplacement of weight plugs in the sole and rear side wall. The attachmentof the carbon-fiber cover is accomplished by insertion of a bladderthrough the hole for the plug in the sole and application of aluminumoxide sand where the carbon-fiber cover contacts the metal base and faceof the head. The bladder is inflated, and the aluminum-oxide sandadhesively attaches the cover to the rest of the club head during aheating process.

Published Japanese Application No. 05-317465 discloses a golf club headhaving a hole cut into the crown part. The hole may be closed with aplate of a transparent and lightweight resin. This device allows theweight of the replaced metal material to be substantially distributed tothe sole, lowering the center of gravity. An initial speed of a ball isincreased and an amount of spin can be decreased, whereby distance canbe increased.

Metal, composite and hybrid metal-composite club heads have longsuffered from poor acoustic properties. That is, golfers are accustomedto—and desire—a particular range in pitch tone generated by the golfball impacting the striking face. Some prior club heads have used a foamfilling in order to alter the sound while attempting to minimize anyadverse impact on performance. While metal club heads have become bettermatched to golfers' acoustic preferences, composite club heads generallylack acoustic appeal.

It should, therefore, be appreciated, there is a need for a golf clubhead having a high COR and improved durability and acoustic qualities,which is cost effective and simple to manufacture. The present inventionfulfills this need and others.

SUMMARY OF THE INVENTION

The present invention provides a golf club head having a high COR thatis durable and has desirable acoustic qualities. The club head includesa body portion, a striking face and a crown forming a hollow cavity ofat least 150 cc in volume. The body portion defines a front opening andan upper opening, and it includes a sole and a side section that extendsrearward of the front opening. The body portion preferably includes arecessed support extended from a shoulder and positioned adjacent to theupper opening to support the crown. The striking plate is secured to thebody portion, enclosing the front opening. The crown is secured to thebody portion, enclosing the upper opening. The crown has a maximumthickness no greater than about 2 mm. The density of the crown is lessthan the density of the body portion. At least one of the striking plateand the crown is attached to the second portion by adhesive bonding, andthe golf club head has a maximum coefficient of restitution of at least0.80.

In a detailed aspect of a preferred embodiment, the body portion ispreferably formed of a metal having a density of at least about 1.8 g/ccand preferably at least about 4 g/cc. The crown has a density between 1g/cc and 2 g/cc.

In another detailed aspect of a preferred embodiment, the crown isformed of plies of composite material having a fiber areal weight ofbetween 20 g/m² and 200 g/m². The weight of the composite crown being atleast 20% less than the weight of a similar sized piece formed of themetal of the body. The composite crown may be formed of an uppermost plyand at least one layer of four plies of uni-tape standard modulusgraphite, the plies of uni-tape oriented at any combination of 0°, +45°,−45° and 90°.

In yet another detailed aspect of a preferred embodiment, the crownincludes a first portion sized to sit on a recessed support of the bodysuch that a side edge of the first portion is proximate to the shoulderof the body portion, thereby forming a junction between the firstportion of the crown and the body portion. Moreover, at least one of theside edge of the first portion and the shoulder of body portion can havea tapered profile thereby forming a depression about the junction. Asurface veil is secured atop the junction, at least partially fillingthe depression, if any.

In yet another detailed aspect of a preferred embodiment, the strikingplate is separately formed and attached to the front of the body of theclub head. At least one of the crown and striking plate is adhesivelyattached to the main body of the club head. The striking plate is madeof metal and is welded to a cast second portion of the body having anopening at its front, with a lightweight crown adhesively bonded to thetop opening of the body.

A method of manufacturing a golf club head having a maximum coefficientof restitution of at least 0.80 is also provided. The method includesforming a body potion of a metal material, the body having walls forminga front, a side section, a sole and a top section, an opening formed ineach of the front and the top section. A striking plate adapted toenclose the front opening of the body is also formed. A crown is formedto enclose the opening in the top section. The crown has a density lessthan 2 g/cc and a maximum thickness no greater than 2 mm. The strikingplate is attached to the body portion, enclosing the front opening. Atleast one of the crown and the striking plate is attached to the body byadhesive bonding. The forming steps may be performed in any order, whilethe striking plate is attached prior to attachment of the crown to thebody. The resulting access to the interior of the nearly complete golfclub head allows final weighting and/or other members to be attached toany inner surface as desired.

For purposes of summarizing the invention and the advantages achievedover the prior art, certain advantages of the invention have beendescribed herein above. Of course, it is to be understood that notnecessarily all such advantages may be achieved in accordance with anyparticular embodiment of the invention. Thus, for example, those skilledin the art will recognize that the invention may be embodied or carriedout in a manner that achieves or optimizes one advantage or group ofadvantages as taught herein without necessarily achieving otheradvantages as may be taught or suggested herein.

All of these embodiments are intended to be within the scope of theinvention herein disclosed. These and other embodiments of the presentinvention will become readily apparent to those skilled in the art fromthe following detailed description of the preferred embodiments havingreference to the attached figures, the invention not being limited toany particular preferred embodiment(s) disclosed.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the present invention will now be described, by way ofexample only, with reference to the following drawings in which:

FIG. 1 is a partially exploded perspective view of a preferredembodiment of a club head in accordance with the invention, depicting acrown separated from a body portion.

FIG. 2 is a cross-sectional view of the club head of FIG. 1, depictingthe crown in place.

FIG. 3 is a cross-sectional view a junction of the crown and bodyportion of the club head of FIG. 1.

FIG. 4 is a cross-sectional view of a second preferred embodiment of agolf club head in accordance with the invention.

FIG. 5 is a cross-sectional view of a junction of the crown and the bodyportion of the club head of FIG. 4.

FIG. 6 is a partially exploded view of another preferred embodiment of aclub head in accordance with the invention, depicting the compositecrown separated from the metal body.

FIG. 7 is a perspective view of a striking face and a body portion of apreferred embodiment of a golf club head in accordance with theinvention, depicting a rear surface of the striking face.

FIG. 8 is a partially exploded perspective view of a third preferredembodiment of a golf club head in accordance with the invention,depicting a crown, including a surface veil covering a top portion ofthe club head, separated from a body portion.

FIG. 9 is a partially exploded perspective view of a fourth preferredembodiment of a golf club head in accordance with the invention,depicting a crown, including a surface veil covering a junction betweenthe crown and body portion, separated from a body portion.

FIGS. 10A-10C are cross-sectional views of a junction of the crown andthe body portion of the club head of FIG. 9, depicting exemplary stepsfor applying the surface veil.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

With reference to the illustrative drawings, and particularly FIG. 1,there is shown a golf club head 10 having a crown 12 formed of compositematerial not yet attached to a body 14 of a golf club head, to enclosean opening 16. The body is formed of any metal, such as an aluminum,steel or titanium alloy, for example. The body may be cast to form afront 18, a sole 20, a top portion 22 and a side portion 24. At thefront, a striking plate 26 is separately formed and attached to thefront of the body in any manner known to those skilled in the art (seeFIGS. 4 and 5). The striking plate may be formed of a different alloy orgrade of the same metal as the body, or the plate may be a differentmetal or a composite material, as desired. If metallic, the strikingplate is welded to the front 18; if made of a composite material, thestriking plate may be adhesively bonded to the front 18.

In alternative embodiments, the metal body may comprise three or moreportions welded together, where the portions are forged, cast or stampedpieces or any mix thereof. Or, the body may be cast except for aseparate sole plate that is attached in the appropriate location. Thebody may also include one or more attached members; such as weightingelements, that may comprise a metal or other material having a differentdensity than the material of the rest of the main body.

The side portion 24 extends rearwardly of the front 18 and has a toeregion 28, a rear region 30 and a heel region 32 formed above the sole20. A hosel 34 is provided at the heel end of the body for attachment ofa shaft (not shown). The top portion 22 of the body 14 extendsrearwardly from an upper edge 36 of the front 18 of the club head, abovethe side portion 24. Thus, the sole 20, top portion 22, front 18 andside portion combine with the crown 12 to form a hollow body having avolume of at least 150 cubic centimeters (cc) and up to 500 cc.

As more clearly shown in FIG. 2, the cast body 14 includes an annularrim 38 at the opening 16 in the top portion 22 that includes a ledge 40that acts as a support member for the crown 12. Alternatively, thesupport member may comprise a plurality of tabs. The size and shape ofthe support member is preferably chosen to minimize the required overlapwith the crown or the mating surface area of the crown and top portion.

Referring to FIG. 3, the rim 38 extends a distance D₁ of at least 7 mmrearward from the upper edge 36 of the front 18, with a shoulder 42defining the ledge 40 which preferably extends an additional distance D₂of at least 7 mm. The rim preferably extends between 8 mm and 12 mm, andmore preferably about 10 mm, from the upper edge 36 while providingadvantages of the present invention. Similarly, the ledge preferablyextends between 8 mm and 12 mm. Preferably, an adhesive such as Hysol®two part epoxy 9460 or, alternatively, 3M® DP460NS, is used to attachthe crown 12 onto the ledge 40, abutting the shoulder 42.

The opening 16 in a central section 44 of the top portion 22 comprisesat least 25% (see FIG. 6), and preferably comprises at least 60%, of thetotal area of the top portion 22. More preferably, the opening is atleast 75% of the total area of the top portion. Thus, there is asignificant weight savings afforded by replacing a similarly sized metalcrown with the crown 12 described herein. The difference in weightbetween the metal and composite materials may be redistributed in theclub head 10 to manipulate the center of gravity of the club head, suchas by providing a weight pad 46 on an interior surface 48 of the sole asshown in FIG. 4. Such a weight pad is preferably formed of materialhaving a higher density (e.g., tungsten) than the material of the body14 of the club head and is attached to the sole 20; although, a weightpad may alternatively be cast as a thickened portion of the sole.

Tables I and II show exemplary materials for the body 14 of the clubhead and the crown 12, respectively. The body 14 preferably has athin-wall construction, wherein the thicknesses of the sole 20 and sideportion 24 is in the range of 0.8 mm to 2 mm and the top portionthickness is in the range of 0.7 mm to 2 mm. The thickness of the frontportion 26 is preferably in the range of 1.5 mm to 4 mm. The crown isalso of a thin construction, having a thickness T_(c) of no more thanabout 2 mm, preferably less than 1.5 mm, and more preferably about 1 mm.In the preferred embodiment of FIGS. 1-3, the thickness of the topportion 22, including the ledge 40, is approximately 1 mm so that theshoulder 42 extends about 2 mm from an outer surface 50 of the topportion to an inner surface 52 of the ledge. TABLE I EXAMPLES OF METALSFOR THE BODY OF A CLUB HEAD Density Ult. Tens. Str. Mod. of MaterialType (g/cc) (MPa) Elast. (GPa) Hardness Mg AZ81A-T4 1.8 275 45 Brinell55 Al 1201 Alloy 2.85 430 72 — Ti 6Al-4V 4.43 950 113.8 Brinell 334Rockwell C 36 Ti 15-3-3-3 4.76 790 82 Rockwell B 95 Carpenter 7.76 1100200 Brinell 318 Custom 455 ® Rockwell C 34

TABLE II EXAMPLES OF COMPOSITE MATERIALS FOR A CLUB HEAD CROWN Modulusof Density Ult. Tens. Elasticity Composite Fiber Material (g/cc) Str.(MPa) (GPa) Carbon Filled Nylon 1.4 103 13 DuPont Kevlar ® 49 Fiber,1.44-1.45 2760 120-125 diam 11.9 um Thornel ® VCB-20 Carbon Cloth 1.881380 138A graphite-epoxy composite material, for example, with a 50% to 70%fiber volume ratio would have a density between about 1.4 g/cc and 1.65g/cc.

A golf club head constructed in this manner advantageously improvesdurability since the junction of the striking plate 26 with the topportion 22 is subject to a lesser force at impact with a golf ball. Theuse of the crown 12 on the metal body 14 also increases COR. Further,the golf club head having a crown on a metal body advantageouslyprovides acoustic qualities judged more appealing to golfers.

In one club head tested by the inventors, a 300 cc hollow body wasformed of a stainless steel alloy. A large area, 1 mm thick crown wasformed of five plies including four plies of a uni-tape of standardmodulus graphite and one ply of a woven graphite cloth. The four pliesof uni-tape were assembled at 0, 45, −45 and 90 degrees and had a fiberareal weight (FAW) of about 140 grams per meter squared (g/m²). Thestandard modulus is approximately 33 Mpsi for the fiber with about 600Kpsi tensile strength. In comparison, an alternative, and moreexpensive, ultrahigh modulus fiber (satellite grade) comprises about 57Mpsi. FAW may range from about 20 to 200 g/m², and preferably thecomposite plies for the crown are in the range of 70 to 180 g/m². Morepreferably, the composite plies for the crown are in the range of 120 to160 g/m².

The resultant mass of the crown 12 is about 10 grams. This is about a50% reduction in the mass compared to a crown formed of the steelmaterial of the rest of the club head. The calculations of the weightsavings must take into account the presence of the ledge 40 with thecrown, as well as the adhesive. Generally, the weight savings is atleast 20% compared to an all metal body. The weight pad 46 may then beadded to achieve a total mass approximately equivalent to an all metalbody.

The crown 12 may alternatively be formed of more or less plies, andinstead of the top ply being a woven graphite cloth, the top ply may beanother uni-tape that is painted to achieve the desired aesthetic lookof the club head. The top ply is preferably oriented at 0 or 90 degrees.The molding of the crown may be performed using methods known to thoseskilled in the art and preferably comprises a matched mold to achieve anet shape that requires little finishing and flash removal prior to itsattachment to the body 14 of the club head.

Another club head tested by the inventors utilized a titanium alloy bodyfor the club head, with a crown 12 formed of a thermoplastic material.Preferably, the crown is an injection-molded nylon or polyphenylenesulfide (PPS) material, using 3M® DP460NS adhesive for attachment to themetal body. The nylon may be used with or without glass or carbon fiberand preferably has a density between 1 g/cc and 1.7 g/cc. Alternatively,the PPS material maybe used with or without glass or carbon fiber andpreferably has a density between 1.3 g/cc and 2.0 g/cc. Replacing thecrown of the titanium alloy club head results in about 35% savings inweight. In general, the weight savings is at least 15% compared to anall metal body.

The replacement of the crown of a metal club head provides the advantageof weight savings and/or redistribution of mass to the sole, forexample. A weight pad on the sole, or elsewhere on the body, may beintegrally formed or be a separately formed and attached mass, theresulting weight being comparable to an all metal club head of the samevolume.

Because of the access afforded by the opening in the top of the clubhead, a rear of the striking face 54 is accessible during manufacturefor the addition of a face reinforcing member 56 formed of metal orcomposite material and securely attached behind the sweet spot, as shownin FIG. 7. Thus, a thin titanium alloy striking face can be strengthenedor otherwise enhanced in performance. Similarly, any number ofadditional members may be attached elsewhere on any inner surface of theclub head.

The use of the aforementioned materials, composite or plastic, for thecrown 12 allows the use of a lighter weight material that may result inthe top of the club head having a stiffness similar to the heavier,metal sole. This stiffness matching may be advantageous for high CORgolf club heads.

The golf club head 10 can be assembled with the aid of adhesive bonding.In a preferred method of manufacture, the striking face 22 is securelyattached to the body 14, enclosing a front opening. While partiallyassembled, final weighting and/or other attachment of other members tothe inner surface of the club head can be preformed, as desired. Next,the crown is secured in place, forming the top section of the club head.Preferably, the crown 12 is of a material having a density less than 2g/cc has a thickness no greater than 2 mm. At least one of the crown andthe striking plate is attached by adhesive bonding to the opening in thebody. In one embodiment, the mating surfaces of the crown and ledge 40may be prepared by sandblasting to enhance bonding. Other steps may beperformed in order to prepare and/or finish the final club head, asknown to those skilled in the art.

With reference now to FIGS. 8 and 9, the golf club head may furtherinclude a surface veil 58 sized to cover the junction between the crownportion 12 and the body portion 14. The surface veil can include pliesof composite material. As shown in FIG. 8, the surface veil can be sizedto entirely cover the junction between the crown and body portion andthe outer surface the crown. Alternatively, as shown in FIG. 9, thesurface veil can be configured to be disposed about the crown to coverthe junction between the crown and the body portion. The surface veilaids in preventing cracking and peeling of the club head's surface. Inthe exemplary embodiments, the surface veil is formed of two additionalplies of the material used with the crown portion, as discussed above.In other preferred embodiments, the crown portion is formed of a firstlightweight material, as discussed above, e.g., carbon fiber plies, andthe surface veil is formed of a second lightweight material, such asdiscussed above, e.g., a glass composite.

With reference now to FIGS. 10A-10C, an exemplary method of attachingthe surface veil 58 is depicted. As shown in FIG. 10A, an obtusedepression 60 is provided at the junction between the crown portion 12and the body portion 14. The depression is preferably formed byproviding a taper to at least one of the side edge 62 of the crownportion and the shoulder 42 of the body portion. In the exemplarymethod, both the side edge and the shoulder are tapered, defining anangle θ, which is preferably greater than 90 degrees and less than 180degrees. The surface veil is attached above the junction such that it atleast partially fills the depression (FIG. 10B). Once in place, theouter surface of the club head undergoes additional treatment, e.g.,grinding and/or sanding, to provide a smooth, finished surface (FIG.10C).

It should be appreciated from the foregoing the present inventionprovides a golf club head having a high COR that is durable and hasdesirable acoustic qualities. The club head includes a body portion, astriking face and a crown forming a hollow cavity of at least 150 cc involume. The body portion defines a front opening and an upper opening,and it includes a sole and a side section that extends rearward of thefront opening. The striking plate is secured to the body portion,enclosing the front opening. While partially assembled, final weightingand/or other attachment of other members to the inner surface of theclub head can be preformed, as desired. The crown is secured to the bodyportion, enclosing the upper opening. A surface veil may also beprovided about a junction of the crown and body. The crown has a maximumthickness no greater than about 2 mm. The density of the crown is lessthan the density of the body portion. Beneficially, the golf club headhas a coefficient of restitution of at least 0.80.

Although the invention has been disclosed in detail with reference onlyto the preferred embodiments, those skilled in the art will appreciatethat additional golf club heads can be made without departing from thescope of the invention. Accordingly, the invention is defined only bythe claims set forth below.

1. A golf club head, comprising: a body portion defining an upperopening and a front opening and having a sole and a side section, theside section extending rearward of the front opening and having toe,rear and heel regions, the body portion having a density of at leastabout 4 g/cc; a striking plate securely attached to the body portion,enclosing the front opening; and a crown secured to the body portionthereby enclosing the upper opening, the crown incorporating compositematerial and having a density between 1 g/cc and 2 g/cc, the crownhaving a maximum thickness no greater than about 2 mm, the golf clubhead having a maximum coefficient of restitution of at least 0.80 and avolume of at least 150 cc.
 2. A golf club head as defined in claim 1,the body portion including a recessed support extended from a shoulderand positioned adjacent to the upper opening to support the crown.
 3. Agolf club head as defined in claim 2, wherein the recessed support is anannular lip surrounding the upper opening.
 4. A golf club head asdefined in claim 2, the crown having a first portion sized to sit on therecessed support of the body portion such that a side edge of the firstportion is proximate to the shoulder of the body portion, therebyforming a junction between the first portion of the crown and the bodyportion, the crown further having a surface veil secured atop thejunction.
 5. A golf club head as defined in claim 4, wherein at leastone of the side edge of the first portion and the shoulder of bodyportion has a tapered profile thereby forming a depression about thejunction, wherein the surface veil at least partially fills thedepression.
 6. A golf club head as defined in claim 4, wherein thesurface veil entirely covers an upper surface of the first portion ofthe crown.
 7. A golf club head as defined in claim 4, wherein the volumeis at least 350 cc.
 8. A golf club head, comprising: a body portiondefining an upper opening and a front opening and having a sole and aside section, the side section extending rearward of the front openingand having toe, rear and heel regions, the body portion including arecessed support extended from a shoulder and positioned adjacent to theupper opening, the body portion having a density of at least about 4g/cc; a striking plate securely attached to the body portion, enclosingthe front opening; and a crown securely attached to the body portionenclosing the upper opening, the crown including plies of compositematerial having a fiber areal weight of between 20 g/m² and 200 g/m² andhaving a maximum thickness no greater than about 2 mm, the weight of thecrown being less than the weight of a similar sized piece formed of thematerial of the body portion; wherein at least one of the striking plateand the crown is attached to the body portion by adhesive bonding, thegolf club head having a maximum coefficient of restitution of at least0.80 and a volume of at least 150 cc.
 9. A golf club head as defined inclaim 8, wherein the recessed support is an annular lip surrounding theupper opening.
 10. A golf club head as defined in claim 8, the crownhaving a first portion sized to sit on the recessed support of the bodyportion such that a side edge of the first portion is proximate to theshoulder of the body portion, thereby forming a junction between thefirst portion of the crown and the body portion, the crown furtherhaving a surface veil secured atop the junction.
 11. A golf club head asdefined in claim 10, wherein at least one of the side edge of the firstportion and the shoulder of body portion has a tapered profile therebyforming a depression about the junction, wherein the surface veil atleast partially fills the depression.
 12. A golf club head as defined inclaim 10, wherein the surface veil entirely covers an upper surface ofthe first portion of the crown.
 13. A golf club head as defined in claim10, wherein the plies of composite material include a fabric ply and atleast one layer of at least four plies of uni-tape standard moduluscomposite.
 14. A method of manufacturing a hollow golf club head havinga volume of at least 150 cc, comprising: forming a body of a metalmaterial, the body having walls forming a front that defines a frontopening, a side section, a sole and a top section that defines an upperopening, the body including a recessed support extended from a shoulderand positioned adjacent to the upper opening; forming a striking plateadapted to be secured to the body and enclose the front opening;securely attaching the striking plate to the body, enclosing the frontopening; forming a crown of a material having a density less than 2g/cc, the crown having a maximum thickness no greater than 2 mm, thecrown adapted to be secured to the body, enclosing the upper opening;and securely attaching the crown to the body, enclosing the upperopening; wherein at least one of the crown and the striking plate isattached by adhesive bonding to the opening in the body, the golf clubhead having a maximum coefficient of restitution of at least 0.80.
 15. Amethod as defined in claim 14, wherein forming the body comprisescasting a metal material, the front and upper openings are formed in thecasting step.
 16. A method as defined in claim 14, wherein forming thestriking plate comprises cold-forming a metal material to the desiredthickness, shape and size, and the step of attaching the striking platecomprises welding.
 17. A method as defined in claim 14, wherein: formingthe crown comprises forming a first portion sized to sit on the recessedsupport of the body such that a side edge of the first portion isproximate to the shoulder of the body portion, thereby forming ajunction between the first portion of the crown and the body portion;and attaching the crown comprising securing a surface veil atop thejunction.
 18. A method as defined in claim 17, further comprising:providing a tapered profile to at least one of the side edge of thefirst portion and the shoulder of body portion has a tapered profilethereby forming a depression about the junction, wherein the surfaceveil at least partially fills the depression.
 19. A method as defined inclaim 17, wherein the surface veil entirely covers an upper surface ofthe first portion of the crown.